Sarcopenia and its relationship with bone mineral density in middle-aged and elderly European men

Summary

The aim of this study was to determine the relationship between reduced muscle mass (sarcopenia) and areal bone mineral density (BMD_a) in middle-aged and elderly community-dwelling European men. Men with sarcopenia had significantly lower BMD_a and were more likely to have osteoporosis compared with men without sarcopenia.

Introduction

In men, the relationship between reduced muscle mass (sarcopenia) and BMD_a is unclear. This study aimed to determine this relationship in middle-aged and elderly community-dwelling men.

Methods

Men aged 40–79 years from the Manchester (UK) and Leuven (Belgium) cohorts of the European Male Ageing Study were invited to attend for assessment including dual-energy X-ray absorptiometry, from which appendicular lean mass (aLM), fat mass (FM) and whole-body, spine and hip BMD_a were determined. Relative appendicular skeletal muscle mass (RASM) was calculated as aLM/height². Muscle strength was assessed in subjects from Leuven. Sarcopenia was defined by RASM at <7.26 kg/m² and by the recent definition of the European Working Group on Sarcopenia in Older People (RASM at <7.26 kg/m² plus low muscle function). Linear regression was used to determine the associations between aLM, FM, muscle strength and BMD_a and logistic regression to determine the association between sarcopenia and osteoporosis.

Results

Six hundred seventy-nine men with a mean age of 59.6 (SD?=?10.7), contributed data to the analysis; 11.9 % were sarcopenic by the conventional definition. After adjustment for age and centre, aLM, RASM and FM were positively associated with BMD_a. Men with RASM at <7.26 kg/m² had significantly lower BMD_a compared with those with RASM at ≥7.26 kg/m². In a multivariable model, aLM was most consistently associated with BMD_a. Men with sarcopenia were more likely to have osteoporosis compared with those with normal RASM (odds ratio?=?3.0; 95 % CI?=?1.6–5.8).

Conclusions

Sarcopenia is associated with low BMD_a and osteoporosis in middle-aged and elderly men. Further studies are necessary to assess whether maintaining muscle mass contributes to prevent osteoporosis.     

Lower bone turnover and relative bone deficits in men with metabolic syndrome: a matter of insulin sensitivity? The European Male Ageing Study

Summary

We examined cross-sectional associations of metabolic syndrome and its components with male bone turnover, density and structure. Greater bone mass in men with metabolic syndrome was related to their greater body mass, whereas hyperglycaemia, hypertriglyceridaemia or impaired insulin sensitivity were associated with lower bone turnover and relative bone mass deficits.

Introduction

Metabolic syndrome (MetS) has been associated with lower bone turnover and relative bone mass or strength deficits (i.e. not proportionate to body mass index, BMI), but the relative contributions of MetS components related to insulin sensitivity or obesity to male bone health remain unclear.

Methods

We determined cross-sectional associations of MetS, its components and insulin sensitivity (by homeostatic model assessment-insulin sensitivity (HOMA-S)) using linear regression models adjusted for age, centre, smoking, alcohol, and BMI. Bone turnover markers and heel broadband ultrasound attenuation (BUA) were measured in 3129 men aged 40–79. Two centres measured total hip, femoral neck, and lumbar spine areal bone mineral density (_aBMD, n?=?527) and performed radius peripheral quantitative computed tomography (pQCT, n?=?595).

Results

MetS was present in 975 men (31.2 %). Men with MetS had lower β C-terminal cross-linked telopeptide (β-CTX), N-terminal propeptide of type I procollagen (PINP) and osteocalcin (P?<?0.0001) and higher total hip, femoral neck, and lumbar spine _aBMD (P?≤?0.03). Among MetS components, only hypertriglyceridaemia and hyperglycaemia were independently associated with PINP and β-CTX. Hyperglycaemia was negatively associated with BUA, hypertriglyceridaemia with hip _aBMD and radius cross-sectional area (CSA) and stress–strain index. HOMA-S was similarly associated with PINP and β-CTX, BUA, and radius CSA in BMI-adjusted models.

Conclusions

Men with MetS have higher _aBMD in association with their greater body mass, while their lower bone turnover and relative deficits in heel BUA and radius CSA are mainly related to correlates of insulin sensitivity. Our findings support the hypothesis that underlying metabolic complications may be involved in the bone’s failure to adapt to increasing bodily loads in men with MetS.

     

New echocardiographic applications for assessing global left ventricular diastolic function

A number of promising and highly technological echocardiographic imaging tools have recently been introduced to assess left ventricular diastolic function (i.e., the capacity of the ventricle to relax and fill). They permit quantification of distinct features of intraventricular blood flow velocity and pressure fields and myocardial tissue velocities. However, accurate interpretation of the new images and clinical indices is still cumbersome, as basic knowledge about intraventricular hemodynamics and ventricular wall mechanics is often insufficient. This review article provides a comprehensive and original overview of the hemodynamical and mechanical events that occur during diastole and discusses how this new information can be used in the clinical and research setting to evaluate diastolic function in the healthy and the diseased heart. It furthermore aims to explain the underpinnings of the techniques in such a way that the underlying biomechanical concepts (fluid dynamics and wall mechanics) become less obscure to cardiologists and echocardiographers and such that the biomedical engineers are given some insights into the avalanche of diastolic performance indices that currently exist.     

A Sertoli cell-selective knockout of the androgen receptor causes spermatogenic arrest in meiosis

Androgens control spermatogenesis, but germ cells themselves do not express a functional androgen receptor (AR). Androgen regulation is thought to be mediated by Sertoli and peritubular myoid cells, but their relative roles and the mechanisms involved remain largely unknown. Using Cre/loxP technology, we have generated mice with a ubiquitous knockout of the AR as well as mice with a selective AR knockout in Sertoli cells (SC) only. Mice with a floxed exon 2 of the AR gene were crossed with mice expressing Cre recombinase ubiquitously or selectively in SC (under control of the anti-Müllerian hormone gene promoter). AR knockout males displayed a complete androgen insensitivity phenotype. Testes were located abdominally, and germ cell development was severely disrupted. In contrast, SC AR knockout males showed normal testis descent and development of the male urogenital tract. Expression of the homeobox gene Pem, which is androgen-regulated in SC, was severely decreased. Testis weight was reduced to 28% of that in WT littermates. Stereological analysis indicated that the number of SC was unchanged, whereas numbers of spermatocytes, round spermatids, and elongated spermatids were reduced to 64%, 3%, and 0% respectively of WT. These changes were associated with increased germ cell apoptosis and grossly reduced expression of genes specific for late spermatocyte or spermatid development. It is concluded that cell-autonomous action of the AR in SC is an absolute requirement for androgen maintenance of complete spermatogenesis, and that spermatocyte/spermatid development/survival critically depends on androgens.     

Ventricular outflow tract obstruction secondary to leiomyosarcoma of the right ventricle

Primary leiomyosarcomas of the heart, particularly those affecting the right ventricle, are uncommon. We report the case of a 70-year-old Belgian woman presenting with the symptoms of progressive exertional dyspnea and left-sided pleuritic pain. A leiomyosarcoma which originated from the right lateral ventricle wall, causing pulmonary outflow obstruction, was diagnosed. Pathology revealed a neoplasm with a myxoid stroma, high mitotic activity and nuclei expressing atypia. Immunohistochemical staining was positive for vimentine and desmin. Seven months after complete surgical resection the tumor relapsed. This case demonstrates the poor outcome, the high relapse rate and inefficiency of treatment associated with primary cardiac leiomyosarcomas. The current literature regarding the incidence, diagnostic techniques, treatment strategies and survival rates of this rare but terminal disease is reviewed.     

Role of ASCA and the NOD2/CARD15 mutation Gly908Arg in predicting increased surgical costs in Crohn's disease patients: a project of the European Collaborative Study Group on Inflammatory Bowel Disease

BACKGROUND: NOD2/CARD15, the first identified susceptibility gene in Crohn's disease (CD), is associated with ileal stenosis and increased frequency of surgery. Anti-Saccharomyces cerevisiae antibody (ASCA), a serological marker for CD, is associated with ileal location and a high likelihood for surgery. We hypothesized that the presence of ASCA and NOD2/CARD15 mutations could predict increased health care cost in CD. METHODS: CD patients in a prospectively designed community-based multinational European and Israeli cohort (n = 228) followed for mean 8.3 (SD 2.6) years had blood drawn for measurement of ASCA (IgG, IgA), Arg702Trp, Gly908Arg, and Leu1007fsinsC. Days spent in the hospital and the costs of medical and surgical hospitalizations and medications were calculated. RESULTS: The median duration of surgical hospitalizations was longer in Gly908Arg-positive than -negative patients, 3.5 and 1.5 days/patient-year (P < 0.01), and in ASCA-positive than -negative patients, 1.1 and 0 days/patient-year (P < 0.001). Median surgical hospitalization cost was 1,580 euro/patient-year in Gly908Arg-positive versus 0 euro/patient-year in -negative patients (P < 0.01), and 663 euro/patient-year in ASCA-positive versus 0 euro/patient-year in -negative patients (P < 0.001). Differences in cost of medications between groups were not significant. The effect of Gly908Arg was expressed in countries with higher Gly908Arg carriage rates. ASCA raised surgical costs independently of the age at diagnosis of disease. Arg702Trp and Leu1007fsinsC did not affect the cost of health care. CONCLUSIONS: Since CD patients positive for Gly908Arg and ASCA demonstrated higher health care costs, it is possible that measurement of Gly908Arg and ASCA at disease diagnosis can forecast the expensive CD patients.     

Do parents understand the medical information provided in paediatric emergency departments? A prospective multicenter study

Aim: We evaluated the extent to which parents understood the medical information about hospitalization of their child in an emergency department and looked for characteristics likely to increase the risk of poor comprehension. Methods: Prospective multicenter study in thirteen paediatric emergency departments. The parents and doctors completed questionnaires based on closed‐ended questions with a common core of four items: reasons of hospitalization, diagnosis, treatment and seriousness of child condition. We evaluated concordance between parents and doctor answers for these items by comparing their responses. Results: This study included 380 parents. Percentage of concordance was 55% for the reason of hospitalization, 78% for the diagnosis, 92% for the treatment, 48% for the seriousness of the condition and 19% for all four items. The mean number of concordant items was 2.76 (CI 95%, 2.66–2.86). Parents whose children seemed not in pain and parents who received additional information from the nurse showed significantly slightly higher levels of concordance with doctor’s answers (2.98 vs 2.66, p = 0.006 and 2.89 vs 2.60, p = 0.004, respectively). Conclusion: This study shows that improvements are required in the clarity of the information delivered to the parents. The assistance of nurses and optimal pain management may help to improve communication.     

Continuing HIV transmission among injection drug users in Eastern Central Canada: the SurvUDI Study, 1995 to 2000

OBJECTIVE: To document HIV prevalence/incidence trends from 1995-2000 and associated risk factors among injection drug users (IDUs) in Eastern Central Canada as an indication of harm reduction strategy effectiveness. METHODS: Nonnominal cross-sectional data (one-time participants) and longitudinal data (repeat participants) were collected using convenience sampling. Participants provided informed consent for face-to-face interviews focused on injection drug use and sexual practices during the previous 6 months; oral fluid samples were taken for HIV testing by enzyme immunoassay. Unique encrypted codes for initially HIV-negative repeat participants permitted incidence rate calculations. RESULTS: In all, 6387 IDUs (median age, 31 years; range, 13-67; males, 73.5%) participated on 9724 occasions. HIV prevalence ranged from 4.7% (95% confidence interval [CI], 2.9-6.5) in semiurban areas to 20.1% (95% CI, 17.6-22.7) in Ottawa, Ontario. HIV incidence was 6.0 (95%CI, 4.5-7.6) per 100 person-years (py) in Montréal, Québec, 3.2 (95% CI, 2.2-4.2) per 100 py in Québec City and 7.0 (95% CI, 4.1-9.8) per 100 py in Ottawa/Hull. Reusing other IDUs' needles was reported by 38.4%. In multivariate logistic regression, IDUs injecting for 6 or more years were more likely to be HIV positive, particularly if cocaine was the predominant drug injected. Multivariate Cox regression revealed higher HIV incidence among those who predominantly injected cocaine, reused others' needles, had injected 6 years or more, injected with strangers, or were men reporting commercial sex work. CONCLUSIONS: These results reveal a volatile situation of continuing HIV transmission among IDUs in Eastern Central Canada.     

Genetic and Environmental Causes of Tracking in Explosive Strength during Adolescence

Purpose: To determine whether the observed phenotypic stability in explosive strength during adolescence, as measured by inter-age correlations in vertical jump (VTJ), is mainly caused by genetic and/or environmental factors. Methods: Subjects are from the Leuven Longitudinal Twin Study (LLTS) (n = 105 pairs, equally divided over five zygosity groups). VTJ data were aligned on age at peak height velocity (APHV) to attenuate the temporal fluctuations in inter-age correlations caused by differences in timing of the adolescent growth spurt. Simplex models were fitted using structural equation modelling. Results: After aligning the data on APHV, the annual inter-age correlations show a clear simplex structure over a 4 year interval. The best fitting models included additive genetic and unique environmental sources of variation. Heritability estimates ranged between 60.8% (CI 37.7%–77.2%) and 87.3% (CI 74.2%–94.0%) for boys and between 76.5% (CI 56.7%–89.0%) and 88.6% (CI 77.8%–94.1%) for girls. Up to 56.4% and 62.8% of the total variation at the last measurement occasion is explained by additive genetic factors that already explained a significant amount of variation at previous measurement occasions in boys and girls respectively. It thus can be concluded that the observed stability of explosive strength during adolescence is mainly caused by a stable genetic influence in boys and girls. Conclusions: Additive genetic factors seem to be the main cause of the observed phenotypic stability in VTJ performance in boys and girls during adolescence.